The proposed research analyzes Mexican migration to the United States to discover why some migrants become long-term, or permanent, settlers in this country, while others continue to shuttle back and forth on a seasonal basis. The study will consider both legal and illegal migrants, as there are significant numbers of each among both resident and seasonal migrants. Data will be collected in three rural Mexican towns and a Mexican urban area, as well as from among permanent out-migrants living in the United States. A team of field investigators will compile migration histories of residents in each of the sample communities. Basic social and economic information will also be gathered from each town resident. A total sample size of around 1200 migrant families is anticipated, including data on 342 families previously collected. Analysis of this data set will be undertaken using three complementary approaches: (1) a life table analysis which depicts how the likelihood of settlement changes with time spent in the migrant force, (2) a cohort analysis which investigates the historical and generational effects which have influenced the settlement of Mexican migrants over time and (3) a multivariate analysis which identifies those variables which are important factors in the settlement process. The final result will be a theoretical model of the process of settlement among Mexican migrants to the United States, specified in terms of a set of structural equations.